One-loop Effective Action up to any Mass-dimension for Non-degenerate Scalars and Fermions including Light-Heavy Mixing

Upalaparna Banerjee; Joydeep Chakrabortty; Shakeel Ur Rahaman; Kaanapuli Ramkumar

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arXiv · 2311.12757

One-loop Effective Action up to any Mass-dimension for Non-degenerate Scalars and Fermions including Light-Heavy Mixing

Upalaparna Banerjee·Joydeep Chakrabortty·Shakeel Ur Rahaman·Kaanapuli Ramkumar

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Abstract

We propose a Heat-Kernel-based method to compute one-loop effective action up to any mass-dimension with arbitrary numbers of non-degenerate scalars and fermions. We demonstrate our prescription by computing the dimension six effective action for arbitrary numbers of non-degenerate scalars, which are consistent with degenerate results presented in prior studies. We have further shown that the effective action for any partially degenerate mass-spectrum can be easily derived from that for the non-degenerate case by employing suitable limits for masses. Our prescription allows us to express the effective action in terms of local operators for the scenarios that involve light-heavy mixing as well, simply by employing an infrared regulator in the non-degenerate action. Along with the formalism, we have also provided the algorithm and outlined the Mathematica program to compute the result up to any mass dimension.

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Upalaparna Banerjee, Joydeep Chakrabortty, Shakeel Ur Rahaman, Kaanapuli Ramkumar. 2023-11-21. One-loop Effective Action up to any Mass-dimension for Non-degenerate Scalars and Fermions including Light-Heavy Mixing. https://arxiv.org/abs/2311.12757

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